1. Field of the Invention
The present invention relates to a recording/playback device that records and reproduces data to and from a recording medium such as DVD or the like, and a recording medium access method adopted in the recording/playback device.
This application claims the priority of the Japanese Patent Application No. 2003-107052 filed on Apr. 10, 2003, the entirety of which is incorporated by reference herein.
2. Description of the Related Art
As a device for recording TV broadcast programs or photographed images, DVD recorders each using a recording DVD as a recording medium have become popular taking the place of the conventional video tape recorders. The recording DVD is an optical disk of 12 cm in diameter and 1.2 mm in thickness and has a recording capacity of 4.7 giga-bytes per side.
There have been proposed recording DVDs of five formats including DVD-R, DVD-RW, DVD+RW, DVD+R and DVD-RAM. “R” stands for “recordable (“write once, read many)” and “RW” stands for “rewritable (rewritable more than once)”. These formats were proposed by the consumer specification association “DVD Forum” (Internet address: URL :http://www.dvdforum.gr.jp/) and another consumer specification association “DVD+RW Alliance” (Internet address: URL :http://www.dvdrw.com/).
The DVD-R and DVD+R are optical disks recordable only once (write once, read many). The DVD-R is an optical disk complying with the format proposed by the DVD Forum, and DVD+RW is an optical disk complying with the format proposed by the DVD+RW Alliance.
The DVD-RW and DVD+RW are optical disks compatible in format with the read-only DVD disk (DVD-VIDEO) defined by the DVD Forum. They are rewritable a plurality of times. These optical disks can be played back by the conventional read-only DVD player. The DVD-RW is an optical disk complying with the format proposed by the DVD Forum, and DVD+RW is an optical disk complying with the format proposed by the DVD+RW Alliance.
The DVD-RAM is a rewritable optical disk encased in a cartridge. It has a low compatibility in format with the DVD-VIDEO DISK, namely, it is considerably different from the other types of DVD. The DVD-RAM is an optical disk proposed by the DVD Forum.
Also, in the DVD-VIDEO Standard proposed by the DVD Forum, a unit called “title” is defined as a data unit. The “title” defined in this Standard is a concept indicating a unit in which one content such as one movie, one musical composition in a music album or the like is reproduced, for example. It is stated in the DVD-VIDEO Standard that up to 99 titles can be recorded to one DVD disk.
The optical disks including DVD-R, DVD-RW, DVD+RW, DVD+R and DVD-RAM adopt the Universal Disk Format (UDF™ ISO/IEC 13346) as a logical format.
Note here that the DVD-RW, DVD-R, etc. adopt formats made compatible with the format defined in the DVD-VIDEO Standard by recording necessary management data and dummy data other than content data (finalizing) after completion of recording the content data.
The UDF file system will not be recorded to any DVD-RW or DVD-R disk before the latter is finalized. That is, any DVD-RW or DVD-R disk, not yet finalized, have no UDF file system recorded therein.
Thus, with any ordinary operation, it is not possible to make a file system-based access control of any DVD-RW or DVD-R disk, not yet finalized.
Also, according to the DVD-VIDEO Standard, referring to a VMGI file as an information file in the title menu allows access from a data base to another file without reference to the file system. Thus, actually, the file system has to have stated therein the top position of each file therein. However, many DVD-VIDEO disks having the top position written in a wrong position as shown in FIG. 1 have been in the market. Referring to the file system in such a disk results in unsuccessful opening each of the files recorded in the disk.